1998 Mercury 9.9/15HP 4-stroke outboards factory service manual, Page 255Get this manual
NON BIGFOOT GEAR HOUSING
4Replace REVERSE gear if gear teeth or clutch teeth are chipped or worn
a-Gear Teeth b-Clutch Teeth
NOTE: When using screwdriver to remove carrier seals, be careful not to scar carrier seal surfaceIf carrier seal surface is damaged, replace carrier5Using screwdriver, remove both seals from bearing carrier